Participants hold candles during a vigil to commemorate the 25th anniversary of the Tiananmen Square crackdown in Hong Kong, China, on June 4, 2014. / Jerome Favre, European Pressphoto Agency

by Peter Shadbolt, Special for USA TODAY

by Peter Shadbolt, Special for USA TODAY

HONG KONG - Many of the 100,000 gathered in this semiautonomous Chinese city on a sweltering Wednesday night are too young to remember the bloody Tiananmen Square crackdown 25 years ago and 1,000 miles away in Beijing, where the mainland government still forbids citizens from discussing the pro-democracy movement.

But young people such as 21-year-old Hong Kong language student Chi Poon say they've been going to Victoria Park for years to attend the vigil remembering the events of June 4, 1989, when the Chinese military moved against student protesters gathered in the capital's giant central square, killing hundreds, if not several thousand. The government never revealed the exact number.

"I have been coming to this event every year for 15 years because it's important to remember the truth about our history," Poon said amid the crackle of amplified music and the screech of slogans. "Some people say that because the massacre happened in Beijing, it's not Hong Kong's issue.

"But this is everybody's issue - we might be from Hong Kong, but we are Chinese, too, and because of this we bear a responsibility."

It's a common sentiment here in the former British colony, which is now governed by the "one country, two systems" doctrine. It grants this special administrative region of China autonomy over everything except defense and foreign affairs.That means free political expression is tolerated, unlike the rest of China.

For mainland Chinese, the vigil was as much about satisfying curiosity as about marking the anniversary of one of the darkest chapters in modern Chinese history.

"I'm here because I want to find out more about the truth of our history - not just about June 4 but about everything that's been hidden from us," said Michel Cheng, a 19-year-old journalism student from Zhuhai studying in Hong Kong. "As more and more students go abroad to study - especially to Taiwan or Hong Kong - they have greater access to material about our history and they can bring this information back to the mainland to let others know more."

Mainland China currently is in the grip of a two-month crackdown on Tiananmen commentary - a sweep that human rights groups say has landed dozens of dissidents and human rights activists in jail. That has prompted many Hong Kongers to want the freedoms of the city-state extended to their mainland counterparts.

For Richard Tsoi, whose group, the Hong Kong Alliance in Support of Patriotic Democratic Movements of China, organizes the annual rally, the issue of Hong Kong's responsibility as an outlet for mainland Chinese dissent remains as important as ever.

"I would say as many as 10% of the people at this rally have traveled here from mainland China," Tsoi said. "Hong Kong has a moral responsibility to these voices on the mainland because we can still freely and legally organize and hold rallies such as these. This is something that still cannot happen in mainland China."

While the Tiananmen anniversary vigil is now a fixture on the Hong Kong calendar, attendance and the crowd's mood are keenly monitored by Hong Kong's pro-Beijing government as a bellwether of Hong Kong's often-complicated relationship with China.

Heightening tensions with Beijing are domestic issues such as elections in 2017, which will for the first time be held under a system of universal voting. Hong Kong has never had a fully democratic system under either British colonial rule or after the handover to China in 1997.

"I think these issues are pushing people to come to this vigil as a means not only to urge democratization in China but also Hong Kong," Tsoi said.

Pro-Beijing action groups, meanwhile, have been more active over the past year, organizing counter-rallies and -demonstrations around the city.

The group Voice of Loving Hong Kong took up a prime location at the entrance to the anniversary rally and, ringed by a cordon of police for its own protection, called on protesters to "forgive and forget."

"People are only being told a part of the story," said group chairman Patrick Ko. "The alliance always emphasizes the university students that were killed in Tiananmen by the army but there were many People's Liberation Army - many young soldiers - that were killed in this encounter.

"What we want is balance, to put the burden of history down and to look to the future together."